如何在屏幕上打印数组的数字(不是ASCII符号)?
MODEL SMALL
STACK 256
DATASEG
Data1 dw 4h, -23h, 3h, 276h, -79h, -345h, 6h, 44h, -77h, 111, 12,10, '$'
CODESEG
Start:
mov ax,@data
mov ds,ax
mov dx,offset Data1
mov ah,09h
int 21h
Exit:
mov ah,04Ch
mov al,0h
int 21h
End Start
此代码打印与数组中的数字对应的ASCII符号。我想打印数字
答案 0 :(得分:3)
我认为您希望获得已签名的数字并且您知道负数是如何编码的(请参阅Wikipedia's article of Ones' complement。MSDOS不提供将数据转换为数字的就绪函数,因此您必须自己创建这样一个函数。主要问题是重复除以10并处理剩余部分。网上有很多例子和解释,用Google搜索:"程序集转换为十进制"。
这是我的方法(TASM):
LOCALS @@
MODEL SMALL
STACK 256
DATASEG
Data1 dw 4h, -23h, 3h, 276h, -79h, -345h, 6h, 44h, -77h, 111, 12,10, '$'
Decimal db 8 DUP ('$')
CODESEG
main PROC
mov ax, @data
mov ds, ax
mov es, ax
mov si, OFFSET Data1
Loop:
mov di, OFFSET Decimal ; Convert WORD to decimal string
mov ax, [si]
call ax2dec_signed
push si ; store SI for later use
mov dx, OFFSET Decimal ; Print the number
mov ah,09h
int 21h
mov ah, 02h ; Print a space
mov dl, 20h
int 21h
pop si ; restore SI
add si, 2 ; next WORD
cmp word ptr [si], '$' ; End of String?
jne Loop ; No: once more
Exit:
mov ah,04Ch
mov al,0h
int 21h
main ENDP
ax2dec_signed PROC ; Args: AX register to convert, ES:DI pointer to target string
test ax, ax ; AX negative?
jns @@J1 ; No: skip the following code
mov byte ptr [di], '-' ; Yes: store the negative sign
inc di ; Increment the pointer to the target string
neg ax ; One's complement, i.e. AX = ABS(AX)
@@J1:
mov bx, 10 ; Base 10 -> divisor
xor cx, cx ; CX=0 (number of digits)
@@Loop_1:
xor dx, dx ; Clear DX for division (don't forget it!)
div bx ; AX = DX:AX / BX Remainder DX
push dx ; Push remainder for LIFO in Loop_2
add cl, 1 ; Equivalent to 'inc cl'
test ax, ax ; AX = 0?
jnz @@Loop_1 ; No: once more
@@Loop_2:
pop ax ; Get back pushed digits
or al, 00110000b ; Conversion to ASCII
stosb ; Store only AL to [ES:DI] (DI is a pointer to a string)
loop @@Loop_2 ; Until there are no digits left
mov [di], '$' ; Store termination character for 'int 21h fn 09h'
ret ; Ret: target string contains decimal '$'-terminated ASCII-String
ax2dec_signed ENDP
END main